Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart is starved of oxygen and heart cells die.

A substance called plaque can build up in the walls of your coronary arteries. This plaque is made up of cholesterol and other cells.

A heart attack may occur when:

A tear in the plaque occurs. This triggers blood platelets and other substances to form a blood a clot at the site that blocks blood from flowing to the heart. This is the most common cause of heart attack.

A slow buildup of plaque may narrow one of the coronary arteries so that it is almost blocked.

The cause of heart attack is not always known.

Heart attack may occur:

When you are resting or asleep

After a sudden increase in physical activity

When you are active outside in cold weather

After sudden, severe emotional or physical stress, including an illness

Many risk factors may lead to the development of plaque buildup and a heart attack.

What causes a heart attack?The correct answer is all of the above. Heart disease can lead to a heart attack when plaque builds up in the arteries that supply blood to the heart. If a blood clot forms, it can block blood flow to the heart. This causes a heart attack. Less often, a heart attack occurs due to a spasm in an artery that supplies blood to the heart.What are risk factors for heart disease and heart attack that you can control?The correct answer is all of the above. Not smoking is the best thing you can do for your heart. You can also lower your risk by staying at a healthy weight, eating a low-fat diet, and getting regular exercise (talk to your doctor before starting to exercise). Taking your medicine for high blood pressure and diabetes also lowers your risk.What are the risk factors you can't control?The correct answer is all of the above. Men are more at risk for heart attacks than women, but a woman's risk increases after menopause. African-Americans, Mexican-Americans, American Indians, Hawaiians, and some Asian-Americans have a higher risk for heart problems. If your parents have heart disease, you are also at risk.Stress can add to your risk of heart disease.The correct answer is true. Some studies have found a link between stress and heart disease. How you deal with stress can also have an effect. If you overeat, drink alcohol to excess, or smoke in response to stress, your risk goes up.Drinking red wine is a good way to lower my risk for heart disease.The correct answer is false. While some studies show that alcohol may have small heart benefits, it also increases the risk of alcoholism, high blood pressure, obesity, and breast cancer. So if you don't drink, don't start. If you do drink, limit it to no more than one drink a day for women and two drinks a day for men.You can't miss signs of a heart attack.The correct answer is false. Not everyone has the classic sign of a heart attack: sudden, intense chest pain. Chest pain may be mild or feel more like pressure or fullness. Not everyone has the same symptoms, so you should know all the signs of a heart attack.What are the warning signs of a heart attack?The correct answer is all of the above. While chest pain or discomfort is the most common symptom, symptoms can be less obvious, and you may not know what's going on. The more symptoms you have, the more likely you are having a heart attack.Women have different heart attack symptoms than men.The correct answer is false. Men and women can have all the same warning signs. However, women are more likely to have shortness of breath, back or jaw pain, nausea, or feel light-headed. These symptoms may occur without chest pressure or pain.If you think you are having a heart attack, you should:The correct answer is call 9-1-1 right away. Minutes count during a heart attack. The sooner you get help, the less damage to your heart. Aspirin can be harmful for some people, so don't take it unless told to do so by emergency or medical personnel.You can prevent a heart attack.The correct answer is true. The American Heart Association recommends the ABCs for heart attack prevention: Avoid tobacco. Become more active. Choose good nutrition.

The pain most often lasts longer than 20 minutes. Rest and a medicine to relax the blood vessels (called nitroglycerin) may not completely relieve the pain of a heart attack. Symptoms may also go away and come back.

Some people (the elderly, people with diabetes, and women) may have little or no chest pain. Or, they may have unusual symptoms such as shortness of breath, fatigue, and weakness. A "silent heart attack" is a heart attack with no symptoms.

You will be hooked up to a heart monitor, so the health care team can look at how your heart is beating.

You will receive oxygen so that your heart doesn't have to work as hard.

An intravenous line (IV) will be placed into one of your veins. Medicines and fluids pass through this IV.

You may get nitroglycerin and morphine to help reduce chest pain.

You may receive aspirin, unless it would not be safe for you. In that case, you will be given another medicine that prevents blood clots.

Dangerous abnormal heartbeats (arrhythmias) may be treated with medicine or electric shocks.

EMERGENCY PROCEDURES

Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to the heart.

Angioplasty is often the first choice of treatment. It should be done within 90 minutes after you get to the hospital, and usually no later than 12 hours after a heart attack.

A stent is a small, metal mesh tube that opens up (expands) inside a coronary artery. A stent is often placed after or during angioplasty. It helps prevent the artery from closing up again.

You may be given drugs to break up the clot. It is best if these drugs are given within 3 hours of when you first felt the chest pain. This is called thrombolytic therapy.

Some patients may also have heart bypass surgery to open narrowed or blocked blood vessels that supply blood to the heart. This procedure is also called open heart surgery.

TREATMENT AFTER A HEART ATTACK

After several days, you will be discharged from the hospital.

You will likely need to take medicines, some for the rest of your life. Always talk to your health care provider before stopping or changing how you take any medicines. Stopping certain medications can be deadly.

While under the care of your health care team, you will learn:

How to take medicines to treat your heart problem and prevent more heart attacks

How to eat a heart-healthy diet

How to be active and exercise safely

What to do when you have chest pain

How to stop smoking

Strong emotions are common after a heart attack.

You may feel sad

You may feel anxious and worry about being careful about everything you do

All of these feelings are normal. They go away for most people after 2 or 3 weeks.

You may also feel tired when you leave the hospital to go home.

Most people who have had a heart attack take part in a cardiac rehabilitation program.

Wright RS, Anderson JL, Adams CD, et al. 2011 ACCF/AHA Focused Update of the Guidelines for the Management of Patients with Unstable Angina/Non-ST-Elevation Myocardial Infarction (Updating the 2007 Guideline). A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Developed in Collaboration With the American College of Emergency Physicians, Society for Cardiovascular Angiograpy and Interventions, and Society of Thoracic Surgeons.
J Am Coll Cardiol
. 2011;57:1920-1959.

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